Ok, i have noticed that alot of people have been having problems with their hp tanks on speeds and a4's. And i keep telling them the same thing. There is a mod you can perform, to make your mini reg able to use hp tanks and have no problems. It is a simple mod that takes about 10 minutes tops. I reccomend it to anyone who has a hp tank, who wants to get a lower velocity, or better performence.

Tools Needed:
Circlip Pliers, you can pick them up at your local hardware store. (Some companies call them Snap Ring Plyers)

Step 1:
Take off your mini reg, and take the circlip out. The circlip is a circular clip that you will see when you look down the mini reg.

Step 2:
Once the circlip is out of the mini reg, take a rag, or anything that will reduce scratches to the mini reg. And put it over the hole and hit it against a table until the internals come out.

Step 3:
When the internals are out, you will see the springs, (they are black.) take the springs off the metal piece. And arrange them so they go facing 2 down, 2 up, 2 down. (())((

Step 4:
You are done Put the mini reg back together and your gun will be able to shoot under 300 fps with a hp tank.

Note: This mod has been approved by an angel tech. In fact, Bob from TAG originally posted how to do this at automags.org awhile back. This mod was done with a hp pmi tank. This mod works with 800 output tanks, i am not sure if it works with any lower.